It is anticipated that mobile networks will have higher speeds and larger capacities with LTE (Long Term Evolution) and EPC (Evolved Packet Core) technologies and the like. Accompanying this progress, it is expected that henceforth content distribution in which content is distributed to various types of terminal including mobile terminals, via a mobile network, will become popular.
Patent Literature (PTL) 1 describes a system in which servers storing identical content, created with a plurality of bit rates, switch bit rates in accordance with an instruction from a receiving terminal, to provide distribution.
Patent Literature 2 describes a video data transmission method in which, in a network environment where the bandwidth of a transmission channel between server and client is not guaranteed, in order to deliver the video without interruption, the client makes data transmission requests to the server as long as there is space in its own buffer.    PTL 1:    Japanese Patent Kokai Publication No. JP2004-172830A    PTL 2:    Japanese Patent Kokai Publication No. JP-H10-336626A